18686718368507 has 4 divisors (see below), whose sum is σ = 21356249564016. Its totient is φ = 16017187173000.

The previous prime is 18686718368491. The next prime is 18686718368519. The reversal of 18686718368507 is 70586381768681.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18686718368507 - 2⁴ = 18686718368491 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18686718368567) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1334765597744 + ... + 1334765597757.

It is an arithmetic number, because the mean of its divisors is an integer number (5339062391004).

Almost surely, 2^{18686718368507} is an apocalyptic number.

18686718368507 is a deficient number, since it is larger than the sum of its proper divisors (2669531195509).

18686718368507 is an equidigital number, since it uses as much as digits as its factorization.

18686718368507 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2669531195508.

The product of its (nonzero) digits is 650280960, while the sum is 74.

The spelling of 18686718368507 in words is "eighteen trillion, six hundred eighty-six billion, seven hundred eighteen million, three hundred sixty-eight thousand, five hundred seven".